text:
What does "a pop-up strike with a steep dive" mean?
In Top Gun Maverick (2022), Capt Pete trains squadrons:

Capt Pete: It's the most difficult stage of the mission.
It's a pop-up strike with a steep dive, requiring nothing less
than two consecutive miracles. Two pairs of F-18s will fly
in a welded wing formation.

What does "a pop-up strike with a steep dive" mean?

These are not military code words, it’s actually self explanatory if you just watch what the airplanes do:  They pop up, then go into a steep dive.
The pop-up was necessary because the ingress was done at low altitude to avoid radar detection.  The aircraft needed to rapidly gain altitude to both clear terrain, and to acquire the target.  The steep dive was also necessitated for delivering ordnance in that terrain.

... and to add another point, unless using high drag ordnance, You cannot deliver high explosive weapons from low altitude because the weapon will impact and detonate directly below the plane, blowing yourself up as well as the target. Popping up and delivering from above 1000 AGL or higher, in a dive, is required in order to allow weapon time-of-flight (TOF), and the delivery aircraft dive recovery to create sufficient aircraft to weapon separation at impact. Generally, for Low drag High Explosive bombs, the weapon must fall for at least 6-8 secs or more to generate sufficient separation.

@CharlesBretana, good point, but I think that's a next level discussion to answer a question about advantages of a diving delivery.  I purposefully try not to over answer sometimes...

@Michale, yes, but in this case, the disadvantages of exposing yourself to AAA and radar guided SAMs vastly outweigh the advantages you mentioned. Unless by "...optimized for delivering ordnance.." you meant deconfliction with the frag pattern.... But as that is the most significant issue involved in the choice to perform a pop-up, it might be "under-answer-ing" not to mention it.

@CharlesBretana, except the OP was looking for a simple definition of the phrase, not pros and cons of the delivery method. (reference their other questions...)  But I removed "optimized" to preclude any debate over technique given the basic terminology scope of the question.

again, true, but if you're going to go beyond the "simple definition", and include the justification or reasons for performing the maneuver[s], then mentioning the most significant one of those reasons might be warranted.

Go ahead @CharlesBretana, I will upvote your answer.  I only dropped 25 lb blue death, it isn't my forte and I'm not interested in going deeper than what I have already said.

I did not downvote your answer. It is correct. I just wanted to add the more important reason we did pop-up attacks as additional information. But thanks for the upvote.  From the early 70s to when I left the service, we practiced low altitude ingress (100- 300 AGL), to pop-up attacks and either low-angle-low drag, (LALD - dive angle less than 30 degrees) or dive bomb (dive angle 30 degrees or greater) weapons delivery attacks, to avoid frag damage.

When in multi-ship formations, attack geometries had to be carefully planned, and executed, to avoid other aircraft frag patterns as well, since the frag debris remained in the air for up to 30 secs, and created a dome shaped area above the impact point that was 3000 feet high and up to 6000 feet in diameter. Flying through this debris from your flight member's exploding ordnance, within 30 secs after weapon detonation, could also easily damage your aircraft.

@CharlesBretana, I was actually trying to suggest that you combine and edit your comments here into an answer of your own...

ahhh, yes, I mis-understood. If my thought is more of a tangent rather than direct response to an op's question, I often just make a comment instead of adding an answer.  At the risk of doing the exact opposite, let me say that I try to focus here on increasing general understanding of aviation issues, and not just to accumulate reputation points..  (I do not, however mean to imply that you were suggesting otherwise - I do appreciate your comments).

@CharlesBretana, no worries, I appreciate your comments, but it was the same tangentiality you noted that caused me to be reluctant to add your information to my answer.

I suspect we are back & forth on this way more than its worth.  If I implied otherwise, my apologies, but my initial intent was not to criticize your answer or imply that it was incomplete by not including the substance in my comment. Your answer was and is perfectly fine as is.  It was just to make that additional info available to readers ...


text:
What does "Splitting the throttles" mean?
In Top Gun Maverick (2022), Maverick flies F14 and evades from enemy flight:

Maverick: Splitting the throttles. Coming around.

What does "Splitting the throttles" mean?

"Splitting the throttle" refers to the application of different power settings on the engines of the aircraft. In the case of the scene from Top Gun: Maverick, the afterburner on the left engine is cut (see image below).

Source: Top Gun Maverick
The purpose of this application of differential thrust is to enhance the yaw rate of the aircraft beyond what conventional control surfaces on the rudders of the aircraft could accomplish. This illustration (albeit for a commercial airliner) illustrates the forces that lead to increased yaw:

Source: Lu et al. "Adaptive Differential Thrust Methodology for Lateral/Directional Stability of an Aircraft with a Completely Damaged Vertical Stabilizer"
A neat breakdown of the manoeuvre from the movie is provided by a former airforce pilot on his YouTube channel: F-14 Split Throttle Dog Fight From Top Gun Maverick | Fighter Pilot Reacts
For some related discussions, see also:

Was differential thrust used in the P-38 to improve turn performance?
Do any aircraft use throttle steering during normal flight?
(Reddit) Multi-engine pilots: do you ever use differential thrust to turn the aircraft in flight?

Interestingly, differential thrust is now receiving increased attention from aerospace researchers for its potential application in electric aircraft with distributed propulsion systems. After all, if the entire leading edge of the wing is covered in small propellers, applying finely tuned amounts of differential thrust might be a useful part of maintaining directional stability in low-energy stages of flight.

Just to be picky, do not forget "that the use of CGI was extensive in the film with the F-14 and Su-57 visualized entirely by computer". I wouldn't use a frame taken from the movie to make a point

Agreed - as @sophit points out, all scenes featuring the F-14 were rendered using CGI (for a lack of cooperation on the part of the Iranian Air Force ).

I feel like the landing of United 232 using differential thrust due to complete loss of control surfaces bears mentioning here https://en.wikipedia.org/wiki/United_Airlines_Flight_232

The eagle-eyed will notice that this CGI is wrong as it depicts an aileron. The F-14 doesn't have ailerons and roll control is provided by the elevons + spoilers on the top of each wing.

It is not a figure of speech, "splitting the throttle" is quite literal. The throttle handle in the F-14 (and in many other aircraft with dual engines) consists of two levers, that control the amount of gas going to the left and right engine. You can see it in this picture:

Under normal circumstances you move the throttle as a whole, causing both engines to have the same level of thrust. But when you move them individually, you literally "split the throttles". This is normally only used when you start the engines (one by one) or in case of fuel or engine problems.
Theoretically it could be used for somewhat creative manoeuvring, almost like you have thrust vectoring, like what Maverick was doing in the movie, especially when you put one engine in afterburner and the other not (with all risks of a flame out), but in real life it was hardly (if at all) used for manoeuvring, as far as I know.

"in real life it was hardly (if at all) used for manoeuvring" There's been at least one famous case where it was used in a commercial airliner that suffered a hydraulic failure.

Are the two levers normally locked or clipped together, with e.g. a pushbutton release?

In commercial aviation the autopilot takes care of this. The autopilot allows a certain split to handle differences in thrust created by the engines. The throttle angle section produces an A/T disengage signal when said adjusted throttle split angle exceeds a predetermined value. (e.g. Boeing 737). This has lead to accidents though.

@MarkMorganLloyd No, the throttles don't have such a mechanism. I don't think any dual engine jet has a latch to lock the throttles together. I know the Thrustmaster Warthog throttle (modeled after the A-10) has such a locking mechanism, but that's just for when you fly a single engine aircraft in your favorite simulator. The real A-10 doesn't have that latch, and neither has the F-14, F-15, F-18, etc.

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What "north wall" is Simpson refer to?
In Top Gun Maverick (2022), Vice Admiral Beau "Cyclone" Simpson speaks to squadrons about enemy terrain:

Vice Admiral Beau "Cyclone" Simpson: Well, Lieutenant, you have a
fighting chance against enemy aircraft. What are the odds of surviving
a head-on collision with a mountain? You'll be attacking the target
from a higher altitude, level with the north wall. Gonna be a little
harder to keep your lase on target, but you will avoid the high-G
climb out.

What "north wall"  is Simpson refer to?

Wow, you really liked this film huh? Me too! Most of these questions today can be answered with context ie/ watching the film.

@Jamiec context is enemy terrain.

The context is terrain, being in enemy territory has nothing to do with it.  This isn't an aviation question, or a military question.  These are plain language terms used in reference to mountains, cliffs, directions, etc.  Don't overthink this!

The target lies in a valley surrounded by mountains so the north wall is... well, the north wall

The target was at the end of a canyon, and the north wall was referring to the wall at the end of the canyon.
The plan was to fly up the canyon, drop the bomb and climb drastically over the north wall. If I remember correctly this scene they were discussing other options.

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What does "Bull's-eye 090, 50, tacked southwest" mean?
In Top Gun Maverick (2022), Capt Pete and his squadrons enters enemy terittory meanwhile
they noticed two bandits on the radar:

Pheonix: Comanche, what's their heading?
Comanche: Bull's-eye 090, 50, tacked southwest.
Wingman: They're headed away from us. They don't know we're here.

What does "Bull's-eye 090, 50, tacked southwest" mean?

Similar Q&A here:  https://aviation.stackexchange.com/questions/95898/what-does-zero-for-twenty-mean?rq=1

"Bull's eye" refers to a pre-briefed geographical ground reference point, probably coded into a map display, that the location of other items of interest will be referenced against. "090, 50" means that the bandits are 50 nm due East (090) of that Bull's eye point. "Tacked southwest" was probably "Tracking Southwest", and means that the bandits current ground track is to the southwest. Missing is an altitude reference... "Angels 12" would mean they are at 12,000 MSL.
A complete radio communication from a ground controller radar site might be:....
Comanche:   "Phoenix, you have two Bandits, Bull's Eye 090, 50, Angels 12, Tracking Southwest"

Nice answer! I'll add that we say "Track" instead of "Tracking" as part of standard ALSA communications brevity, so the call is "...Angles 12, track Southwest." The other version "Tracking" communicates that an enemy air defense system is following a friendly aircraft. You can learn more about brevity terms here: https://www.alssa.mil/mttps/brevity/


text:
Why does speed lose out to capacity?
The Concorde had a maximum speed of 2.05 Mach, carrying about 96-128 passengers. The Airbus A380 can achieve a top speed of 0.95 Mach with more than 500 passengers on board. This means roughly 5 times more passengers can be accommodated by compromising half of the top speed. So, why does speed lose out so much to capacity that it ultimately becomes unfeasible to operate a supersonic airliner?

A clarification: by "why does speed...airliner" I mean, why manufacturers shifted their focus from speed to capacity.

There is somewhat flawed logic in your question, implying there is relation between speed and capacity. The ATR-42 has a top speed of Mach 0.55 and can carry about 42 passengers. Comparing it to the Concorde we see that it goes 4 times faster with twice as many passengers. This must be a quadratic relation. We therefore know that the A380 should be able to fly Mach 7 if they only tried a bit harder.

@DeltaLima Based on your numbers, it seems that faster-than-light travel should be possible for any vehicle containing more than about 77,000 passengers. Why are large sports stadia so slow?

@DavidRicherby: Compatibility with existing runways. Most are just not long enough to get a sport stadium up to speed.

@DavidRicherby If the OP's logic is correct those large sports stadia should be moving with the speed of the tectonic plates which is indeed so and hence proves he's right. I retract my comment :-)

@DeltaLima: actually on these numbers, a sports stadium moves faster than a tectonic plate, as demonstrated by the fact that both the Giants and the Jets move faster than New York City. Similarly, the 49ers stadium has recently left San Francisco. The long-term record is either the Cards or the Rams, I forget which, and the Raiders stadium is migratory.

@SteveJessop Depends on your frame of reference. :) If your frame of reference is relative to the center of the Earth, the teams who have moved West are slightly slower than the others, while the ones who have moved East are slightly faster than the others. :)

Because on most flights, you spend as much time, if not more, getting to the airport, dealing with security checks, boarding, taxiing, &c as you do actually flying.  So doubling the speed of the plane only gets you a 25% decrease in travel time.

Which means, roughly 5 times more passengers can be accommodated by compromising half of the top speed. So, why does speed loses out so much to capacity that it ultimately becomes unfeasible to operate a supersonic airliner?

I think you are asking, "why do supersonic aircraft have such low capacity"?
To travel faster than the speed of sound you need to have a very sharp nose and minimal area exposed to the forward direction, to minimize the generation of shockwaves. Shockwaves are bad for people on the ground (the 'sonic boom' effect) and they are terrible for fuel efficiency. Second you really do not want to trap air on flat surfaces facing forwards, because the air will get squashed in the supersonic flow and heat up a lot (like when you blow up a bicycle tyre or a football it is warm afterwards, or when the space shuttle re-enters the atmosphere). Again this is an enormous drag and having hot air flowing around your aircraft causes problems with the structure (Concorde used to grow by 300 mm during flight because of the heat).
Since you cannot be wide and you cannot be tall (without being aerodynamically inefficient), you need to be very long if you want lots of people. And then you have other problems.
The design and construction of Concorde was never a commercial project, it was funded by two governments almost as a vanity project, as a prototype or as an experiment. Then it was given for free to two airlines to use as they wanted.
So unlike the A380 and the B747, no one has ever said "now we try to maximize the economics and the capacity of our design": that never happened. All they ever asked was "How do we make this work!?"
Whereas the subsonic aircraft get a lot of time, money and thought spent on how to make them more economical to use by filling them with more passengers.
For more information I recommend this interview with a former Concorde pilot: http://omegataupodcast.net/2015/02/166-flying-the-concorde/

Also, Concorde was developed 40 years ago. Are some more efficient supersonic Airliners possible today?

I am sure that these days a far more fuel efficient supersonic engine could be built for passenger operations. And I do believe there would be a market for it on say LON-NYC or even maybe LON-DXB. But designing supersonic aircraft is quite different to designing subsonic ones; and then you have all the difficulty of modern safety regulations without being able to demonstrate you are relying on old, proven designs; and then there are very few routes where it could work profitably so you have very high development and maintenance costs spread over a small number of airframes.
Basically, it isn't worth the risk to anyone to make it.

The technical (size) constraints feed into economic/business ones as well: Something like Concorde costs a lot more per seat-mile which comes with correspondingly higher ticket costs (and if you don't fill the plane you may be operating the flight at a loss). By comparison a 787 hauls more people and has a lower per seat-mile cost: You can attract more people at a lower ticket price, and reach a profitable capacity more easily.

@voretaq7 I agree, but on a small number of routes such as LON-NYC, the operating costs were not hard to meet. The famous story at BA is that they used to do surveys of Concorde pax to find out what they should charge, but almost no one knew how much they had paid in the first place! So BA increased the price with zero effect on demand.

Cost for last journey of concorde from JFK-LHR was USD2999+ taxes. While today its less than USD 1000.

@anshabhi Are you comparing to First class?

@Calchas Yes, Concorde was something of a special case (mainly business travelers, with pretty liberal travel budgets). The cost only really becomes an issue when we're talking personal travel (something like JFK-LAX to visit grandma where you have to decide between $600 per person on a 757 or $1000 per person on a SST to shave 2-3 hours off the trip), or when your company's travel budget is stingy and gives you a 3-hour layover in Phoenix waiting for a connecting flight :)

@voretaq7 Good point, no reason to make your airplane too big if you only expect a small number of pax to be able to afford it

@Calchas even better, BA originally charged the same for Concorde as for their regular service and couldn't sell the tickets. When they raised the price, and launched a campaign promoting it as a "premium service" and built an image of Concorde as the ultimate in luxury and class, people started buying the seats and Concorde became profitable. Those people hadn't wanted to fly in the cramped Concorde seats before the price went up, but now they could brag about buying the expensive premium service their friends/competitors couldn't afford...

Basically, it isn't worth the risk to anyone to make it. Has someone told Elon Musk about this yet?

@jwenting Actually that makes perfect sense. Underpricing a premium service is the same as trying to sell an overpriced value service. The pricing must match the market segment. And knowing what it is you are selling does help... Not in marketing, and I have still run to people wondering why making their products cheaper dropped sales... It really does happen, weird as that sounds.

@VilleNiemi I don't say it doesn't make sense, but it did surprise them. Having worked in high profile companies where people acted on the idea that "expensive is good, more expensive is better" when making purchase decisions I'm all too familiar with the mindset that the most expensive product MUST be the best one.

@jwenting Seems reasonable. It suggests the market has already evaluated the product and found the price tolerable. Therefore, the product must be really great.  ;)

@jwenting Well, on a competitive market you generally get what you pay for. Meaning if you buy more expensive, you are less likely to get fired for buying a lemon. There used to be saying "Nobody got fired for buying IBM" to that effect in the early neolithic when IBM still sold PCs. Additionally, more expensive the decision was, the more committed your bosses are to it and less likely there is to be failure that you will get blamed for due to inadequate budget or leadership failure. Failures caused by saving money are generally very expensive.

@VilleNiemi indeed. "If IBM makes it, buy IBM. If not, buy the most expensive" was for a long time the standard procedure in corporate purchasing departments.

Boom Technology is developing a 3-engine mach 2.2 all business class 55 seat supersonic aircraft. It has 76 orders with a significant deposit, including firm orders from JAL and Virgin. Introduction is scheduled for 2023. Someone is crazy enough to try and build one. I hope they find an engine! - https://boomsupersonic.com/airliner

There are a few questions here but ill mainly address this one

Also, Concorde was developed 40 years ago. Are some more efficient supersonic Airliners possible today?

First off there is at least one company who has said they are working on this mainly for the high end market but working on it none the less.
Boeing took a crack at it years ago but the program was eventually stopped.
The primary reason that no super sonic aircraft have been developed since the Concorde is because the FAA prohibits super sonic flight over land. This means a few things. First off you limit your self to routes that are primarily if not only over water. Which means that you limit who you can sell the craft too. This of course makes it unattractive to a company from a production/cost stand point. Now you are probably thinking, why not fly sub sonic over land then hit the throttle when we turn out over water. This sounds great but generally the aerodynamics that make a super sonic plane a super sonic plane are not great at the lower speeds in the spectrum. Could something maybe be designed, sure, but the market is clearly limited.
Cost is the main driving factor in aviation. It is cheap to develop a new car and bring it to market but planes require a much more stringent process which reflects in their price. As such airlines (and even GA consumers) want to get as much out of a plane (time wise) as they can. Supersonic aircraft experience stresses and heat that their subsonic counter parts don't. This makes them unattractive to potential buyers since the planes need more support to be kept in the air.

Modern (as in the last 30 years or so) fighter jets are designed specifically for desirable trans-sonic performance at both high subsonic and supersonic speeds. the F-22 can supercruise (supersonic speed at military power, no afterburners). So you're right on both counts here; we have the technology, but cost and U.S. federal law are huge reasons it hasn't been done since Concorde.

Most other countries prohibit supersonic flight over land, too (some, but not all, have exceptions for military aircraft).

I think this is a question about "how to design/build an airplane"...
First of all, the Concorde was designed to have a 2.05 mach velocity and carry on 96-128 passengers, and the A380 was designed to have a 0.95 mach velocity and carry on ~500 passengers.
This does not means that the A380 compromisses velocity over capacity. Someone could design and build an airplane to carry on the same amount of passengers as a A380, but fly as fast as the Concorde did. This hypothetical airplane must be VERY dificult and expensive to build and very expensive to operate, and surely non airport on Earth has ben build to handle it.
When you design an airplane, the first thing you must have in mind is "what is this plane for?", because you are trying to "supply a demmand", and not trying to see "who would buy this s***t?".
When an airline buys a plane, they have in mind

This plane is going to fly from this airport to that specific airport in that specific path.
XXX amount of passengers are going to buy tickets.
To maximize the incoms and minimize the outcomes the plane I should by is: ***

The main reason that no commercial supersonic flights are aviable today is because the are very expensive and don't have many routes to cover. I mean, althou some airlanes would buy 3 or 4 "Concorde like" planes, any plane manufacturer will design and build just a houndred planes. It's just not profitable.

"An engineer is a person that can build with a dollar what any idiot could build with ten". If you subscribe to this definition of "engineering", the Concorde wasn't even engineered.

Planes aren't necessarily bought for the specific purpose of flying a single route their entire careers, especially when you talk about U.S. domestic air traffic. It happens with the big widebody airliners largely because there are very few routes that call for such a large plane in the first place (ultra-long-haul, mainly). On domestic routes, it's usually more economical to fly more, smaller jets than fewer larger ones. It also creates some convenience for the passengers, as they have their choice of flight times.

@KeithS You are totally correct. But I think you are missinterpretating a little my words. Planes are not necessarily bought for an specific purpose, but are bought to supply specific necessities. I mean, an airline wont buy a plane that result very small or very big.  They know what they need.

Very true, and correct. Airlines buy what they need to service the routes they plan, taking into account flight range, passenger demand, flight frequency, airport capacity (fewer flights per day between two congested airports with a widebody might be a sound plan, but some airports just can't accommodate one) etc. Right now, airlines are more or less keeping the "smaller planes, more flights" model, but Airbus predicts that airport congestion will require a switch to widebodies on major U.S. domestic routes in the next couple of decades,

Mainly, cost.
Flying supersonic consumes a vast amount of fuel. In this day and age of bargain airfares, a London-NYC round trip ticket on Concorde would set you back anywhere from USD8k-20k, depending on what sort of discount you could get. At the same time, the bargain airlines were offering $500 round trip tickets over the same route. A good deal of Concorde's passengers were first class who used frequent flyer miles to upgrade to Concorde.
The 787 has become a best seller, because it offers 15-20% better fuel economy than older models. That's what the customers want, not half the time at 10-20 times the cost.
Also, due to the fact that most nations have banned supersonic flight over their land due to the sonic boom, for reasons that the Oklahoma City supersonic tests revealed in 1964, supersonic flight is limited to over ocean flights only. It couldn't be used on the very busy long over land routes, such as transcontinental US, or Europe to Asia.
Building a very complex aircraft that could only operate on a few routes limits the number of aircraft that could be sold, which adds considerably to the development and operational costs.
It is no coincidence that the Concorde, TU144, and Boeing 2707 were originally envisioned when oil was $3/barrel, in the early 1960's. When oil prices shot up in the early 70's, making supersonic flight hideously expensive, the 2707 was killed off and the TU144 sort of killed itself. Since the Concorde was already built at that point, they put it into production, but rising energy prices limited it to 14 aircraft for the flag carriers of Britain and France. The rest of the airlines bailed due to the very high cost.
It's not that we have regressed technically since the 1960's. More that the price of energy increased to the point where a supersonic airliner isn't economically feasible.

The social environment and world events also came into play for the Concorde.
Read 1/2 down in this article:
https://www.theatlantic.com/technology/archive/2015/07/supersonic-airplanes-concorde/396698/

Whereas most Concorde takeoffs and landings were warmly attended,
  others became protest sites. Money aside, Concorde had other
  challenges. Noise and environmental concerns shrunk the open skies.
  Many countries banned it from their airspace because of the loud sonic
  boom it produced. As a result, nearly half the planned routes, notably
  those over land, were off-limits. The crucial “Blue Ribbon” route
  between New York and London was miraculously approved in 1977. Whereas
  most Concorde takeoffs and landings were warmly attended, others
  became protest sites, with signs reading: “Ban the Boom” and “Save the
  Ozone Layer.” The Anti-Concorde Project founder Richard Wiggs was the
  face of this movement, publishing advertisements, organizing
  demonstrations, and calling Concorde “elitist and inherently unsafe.”
  Aviator Charles Lindbergh, the first to fly transatlantic in 1927,
  became an active environmentalist later in life and lobbied against
  supersonic travel. Ozone emissions and atmospheric pollution were the
  greatest environmental concerns and turmoil over the loud, disruptive
  boom that had the power to break windows were constant contentions.

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text:
Why is the manufacturing process of an aircraft mostly manual?
Why is the manufacturing process mostly done by humans, and not by robots as in case of most other industries?Video

What makes you think that most other manufacturing is done by robots? China employs upwards of 100 million people in manufacturing jobs. Over 12 million Americans work in manufacturing. 10% of the UK workforce is in manufacturing. Modern processes may use 'robots' for efficiency but humans are still needed. Perhaps it can be compared to modern aircraft being able to automatically do the job of a Flight Engineer, but you still need two pilots (for now...).

Frankly saying Thismade me think like that!

Although robots have taken over many jobs in the process of manufacturing things like cars, airliners are much larger and more complex. In some ways it has more in common with constructing a building than assembling a vehicle. There is a much larger variety of tasks to be performed over a much larger area.
That being said, many parts of the manufacturing process are completed by robots. For example, Gemcor makes machines that automatically drill aircraft wings and fasten them with rivets and bolts.

Robots are also used in manufacturing large composites. You'll notice how massive these machines are, and they are only completing one task on one component. They are very good at tasks that require one or more of force, repetition, and accuracy.
However, so much of the process is not economical to be done with robots. A robot specializes in one task or one type of task, while humans can do many different tasks. Many tasks involve working in tight spaces, which humans can do better than a large robot. Tasks like installing wires require dexterity as well, which humans are better at.

They promised us flying cars in the 21st century. Instead we got flying buildings? Close enough...

Economy of scale is a factor. Even the most produced airliners, the B737 and the A320, are delivered in a few hundred units every year. A robot is an investment - a big one, since robot costs are proportional to size, task, precision etc. Divide the investment cost over the production number, and when is the investment going to be recouped?
And the work that the robot must be programmed to do is highly skilled work, which for a large part takes place inside the aircraft: wiring through holes in the stiffeners, tubing for the air conditioning aystem etc. Highly complex work in constrained spaces divided by not many units makes poor economics for automation.

Just for comparison, a typical car factory will produce well in excess of a hundred cars every day.

@Sanchises exactly.

Here in Russia we have two main reasons:

Conservatism in Aviation sphere.
Costs.

All that is new is very difficult to promote in Russian aviation. And I'm talking not only about aircraft. The main reason for this is red tape. And "reliability"...
It is assumed here that if something works well for many years, then it is better to leave it that way and do not change anything.
As was mentioned above: Economy of scale is a factor. It's really true!

With robotics, it's cost versus expected return.
The cost of the robot is directly related to the complexity of the task. For example, a simple screw driving robot can cost upwards of $100k, plus line testing and adjustments that add at least another 10k-20k - despite high tech, there is still a substantial element of trial and error to assembly line robotics.
The expected return is replacing a human - what is the cost of the human, how many times does the human make a mistake, and can the robot operate faster than the human? In the aforementioned screw driving robot, it replaces a human that costs the company $50k-60k per year (by the time one factors in benefits costs, etc...) and operates faster than the human which pushes up line throughput, so it pays for itself after about 1 year.
Robots can still make mistakes, as the components of the robot wear or fail.
Volume of production is also a major factor - a robot is cost efficient in high volume and simple tasks, as the benefit is directly tied to a per unit cost reduction. The fewer units, the less the benefit.
Humans can think during the process, can analyze, suggest improvements and spot potential problems. while the robot can only do what it is told to do. The more complex the task, the more this ability becomes important.
With aircraft assembly, you have relatively low volume and very high complexity. Building robots to take over the more complex assembly tasks would be extremely expensive, with not enough per unit cost reduction to justify the expense.

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text:
Were early military planes not pressurized?
I just heard that  1930s-40s planes such as the B-17 were not pressurized. Is this true? If yes, then how did the military men survive at heights of 30k ft?

The slightly more recent (but still WWII) B-29 did have a pressurized cabin.

There were a few problems:

Pressurization (while not impossible) was difficult requiring extra effort. It also increased weight and complexity.
Pressurization was still a relatively new technology at the time. For reference, the first pressurized commercial aircraft, the Boeing 307 Stratoliner, made its first flight later the same year (1938) as the B17. Note that it was developed from the B17.
There was an incredible amount of openings on early planes for gun turrets, bomb bays, etc. Sealing these off airtight would have been a impractical nightmare. You would traverse the bomb bay move to the back and front of the plane.
It's also better from a reliability standpoint- it's pretty easy to damage and make a hole in the fuselage, but everybody having their own oxygen masks removes that single point of failure.
While perhaps (I imagine) not incredibly comfortable for long duration missions oxygen masks worked fine.

30,000ft corresponds to around 9,200m, although that altitude is a ceiling defined by Boeing. With full load, they never achieved those altitude and hung around a lot lower. While I can't verify it, these forum posters appears to suggest that 19,000ft-28000ft with bombs was more common.
To do the math, the partial pressure of oxygen at sea level is around 0.21 bar. If you're being fed 100% oxygen through your mask, this is the same pressure as at 11,000m.

Photo by Margaret Bourke-White, Sept. 1942, from the LIFE Archives.


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Why is it more difficult for ATC to manage a larger airliner?
After playing a few ATC simulation games, and reading at a few places (don't remember where), I am certain that it is more difficult to manage a larger airliner for the ATC.
Suppose that one A320 and one A380 is trying to land at a certain airport. In another case, if two A320s are queuing up for landing, what extra precautions would the ATC have to take in first case, mainly in separating the aircraft and ensuring that they are on time?

They must leave a greater amount of time in between landings/take-offs as the size of the aircraft increases due to wake turbulance
There were historically 3 classes of aircraft for the purpose of wake turbulance classification

H (Heavy) aircraft types of 136 000 kg (300 000 lb) or more;
M (Medium) aircraft types less than 136 000 kg (300 000 lb) and more than 7 000 kg (15 500 lb); and
L (Light) aircraft types of 7 000 kg (15 500 lb) or less.

With the introduction of the A380-800, where it is near MTOW, a fourth category has been added

Super Heavy for Airbus A380-800 with a maximum take-off mass in the order of 560 000 kg

How much time must be left? Well that depends, for an A380:
Arriving Aircraft

MEDIUM aircraft behind an A380-800 aircraft — 3 minutes;
LIGHT aircraft behind an A380-800 aircraft — 4 minutes.

Departing Aircraft

3 minutes should be applied for a LIGHT or MEDIUM aircraft and 2 minutes for a non-A380-800 HEAVY aircraft taking off behind an A380-800 aircraft when the aircraft are using:

the same runway;
parallel runways separated by less than 760 m (2 500 ft);
crossing runways if the projected flight path of the second aircraft will cross the projected flight path of the first aircraft at the same altitude or less than 300 m (1000 ft) below;
parallel runways separated by 760 m (2 500 ft) or more, if the projected flight path of the second aircraft will cross the projected flight path of the first aircraft at the same altitude or less than 300 m (1 000 ft) below.

Source for timings: http://www.skybrary.aero/index.php/Airbus_A380_Wake_Vortex_Guidance

Multiple reasons I can think of (but I'm no pilot so I may be wrong!):

Bigger aircraft are more constrained in terms of which runways they can accept clearances to land on & take off from
Bigger aircraft typically need more room to maneuver into holding patterns, change Flight Levels,  make turns etc.
Larger aircraft cause more wake turbulence and need to be provided larger separation behind them especially if the following aircraft is much smaller in size
Bigger aircraft need longer to slow down and are constrained in which taxiways they can exit via. or whether they will accept LAHSO clearances
Bigger aircraft (especially the really big ones) typically have fewer options in terms of parking bays, ramps, tugs etc. that can service them which imposes further restrictions for ramp controllers and ground movements.
Bigger aircraft have higher stall speeds in general and higher landing speeds too. So a controller is limited in how much (s)he can ask a Heavy to slow down while executing his plan.

Would any size airliner accept a LAHSO clearance? For that matter, would any jet accept (or be offered) a LAHSO clearance? Also, larger airliners don't necessarily land much faster than smaller ones. Depending on how much weight it's burned off in flight, a 777 might actually land slower than a 737.

@reirab -- they'd check their performance charts -- the LAHSO distances at some airports are longer than the full runway length at other jet-served airports (such as DCA or MDW).

@reirab: Stall, and landing, speeds depend mostly on the design cruise speed of the aircraft, so since most jet airliners are designed to cruise at M0.85, they also land at similar speed. Turboprops are designed for lower speed and have correspondingly lower landing speed.

@JanHudec Right, that was my point. Landing speed depends mostly on design cruise speed, weather, and current weight relative to MTOW, not so much the actual size of the aircraft. Small jets generally land at speeds very similar to those of heavies, contrary to the implication of point 6 above. Of course, turboprops (and especially pistons) will generally be slower, due to being designed for lower flight speeds.

@reirab, I was just confirming it, yes.

I wouldn't say more difficult. But it definitely needs extra care. That's mostly for 2 reasons:

Inertia. Bigger aircraft have more mass, more inertia and thus cannot change their kinetic status easily. So ATCOs should have that in mind when vectoring aircraft and should issue commands earlier.
Wingtip vortices. Wingtip vortices are a function of lift. More lift is needed to keep a heavier aircraft flying, so this aircraft will cause more powerful wingtip vortices. Those can be dangerous and pose a threat for planes landing right behind heavier ones.


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How is a runway inspection carried out?

During the Concorde's takeoff run, this piece of debris still lying on the runway, was run over, cutting a tyre and rupturing it.  A runway inspection, scheduled for 15h, had not been carried out.

How is a runway inspection carried out? How often is a runway inspection done? And, what all is checked in a runway inspection?

The answer will differ a bit from airfield to airfield but here is a typical inspection procedure for East Midlands in the UK(EGNX).
The inspection is carried out first thing in the morning and last thing at night, then at 2 hour intervals throughout the day.
It is carried out by a vehicle in co-ordination with ATC who might shut the runway down for a few minutes.  The vehicle must get permission from ATC to enter the runway and must report on leaving.
Approach will co-ordinate the arrivals, by extending them slightly, so that no-one has to hold or go around (hopefully).  It is also possible to do half the runway as a departing aircraft lines up, leave the runway at a turn off, wait for the departing aircraft, then complete the inspection before the next departure.  There are several ways to do it without causing disruption.
The vehicle enters the runway and drives the complete length visually checking the items on the inspection list.
The document gives you a complete list of items to check but essentially it is:

Clear of FOD.
Markings and signs in good condition and visible.
Lighting working and undamaged.
Runway surface not damaged.
Oil and fuel spills.

Almost the same procedure is also used at KPNE where I used to fly out of. I have been held for it a few times and watched it happen.


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Is the commonly assumed UFO (flying saucer) design aerodynamically efficient?

Is this design, a circular disc (or flying saucer) slightly humped on the top and bottom aerodynamically efficient? And if, we are able to use it for commercial purposes , would they give a better efficiency than existing aircraft?
This article states that this would be a better design. Is this true?

I am just an enthusiast, who is pretty familiar with physics. But, still please keep your answers little simple..!!

That article does NOT state it would be a better design. In outer space there is no aerodynamics as there is no air. If you are familiar with physics then how is the design going to generate lift?  You do have many interesting questions but this one is bit out there.

@Blam Just about any shape can generate lift if it can accelerate air downwards.  The Canadian Avrocar is an example of a disc which generates lift, as is a Frisbee.  Whether it's efficient or not is a separate matter.

@Simon Agreed. A brick can fly if you propel it fast enough. Most fighter aircraft are proof of that. I disagree that this question is really off-topic. This one may be a little odd, but questions about aerodynamics are explicitly on-topic here.

Would the aliens care? It only needs to be efficient design for hyperspace/warp travel; they don't care about the last 100km or so.

@Blam I am not talking about space. Just the atmosphere (troposphere/stratosphere).

OH just a local home built UFO designed to stay close to home.  Again nothing in that article states a better design.  Why sensationalize and misstate?

@Blam: Lift is irrelevant, since the "flying saucer" type of UFO presumably has anti-gravity & a reactionless drive :-)

I'm guessing the efficiency of a (non-rotating) disc like this wouldn't be very high, on its own; because the "wings" are effectively of very low aspect ratio, and there would probably be quite a lot of induced drag from the "wingtips" at normal speeds. But using this profile on the body of a blended wing design with more conventional wings would be a completely different matter. Any proper aerodynamicists in the house?

@anshabhi I edited one of my answers from a month ago with a picture and reasons why it wouldn't be efficient. I think it is a very good question.

In (all?) sci fi this is backed up with some exotic propulsion system, such as anti-gravity, etc.  This design would not serve much of a use for us Earth folk.

@Ethan sorry.. I am just very less active on Stack Exchange these days and and further I don't get any notifications if someone edits their answer on one of my questions.

@Ethan you have put some very sincere efforts in writing the answer.. And, I salute them!

@MartinJames becaue a spacecraft needs to be able to return safely to its home planet which almost certainly has an atmosphere. A reusable spacecraft that doesn't blast off like a rocket would need lift to get off the ground and get up to speed before going with throttle up to reach escape velocity(or at least orbital velocity).

The correct answer is no. A ufo with its circular shape has trouble traveling through the air. It struggles to travel through the air like a city bus, which  gets 2-6mpg. Depending on the amount of thrust this object has depends whether it can lift up into the air. But it would not be efficient because of the amount of fuel it needs to consume to pass through the air, its kind of like a flying city bus not really very aerodynamic and is terrible in efficiency. If this was powered by human technology it would not be efficient considering if its made by humans, if it was made by aliens then maybe it would be efficient, but that information we do not know and probably never find out in our lifetime and we don't even know if aliens exist. You also have to consider the design of this certain ufo. This shape cannot develop lift and runs fully on thrust, which also decreases its efficiency because of gravity pushing down on the flying object. Imagine an airliner without wings and how much efficiency you loose without the wings.Wind tunnel test for a circular shape. If a ufo was so efficient it would have been used on our current airliners. Now lets go into problems with a ufo being an airliner.

Its round circular shape would have trouble fitting into modern day terminals
Much thrust needed for vertical takeoff and landings
Not much room to store fuel
It would be very difficult for pilots to fly this object compared to modern day airliners
Airports would be redesigned for these objects which costs billions of dollars
Only has one engine to push the object instead of generally 2 on an airliner
Lots of weight the one engine needs to lift
One engine would be very difficult to do maintenance work on
The amount of money needed to be invested into this type of airliner
No horizontal or vertical stabilizer
Cost even more than the Concorde for maintenance
The costs to buy one of these would be 5x the price of a regular airliner
Amount of gas needed would be more than the Concorde
Amount of money needed to invest in this kind of technology, which doesn't even exist yet
No airline would want this because of the price
The whole ufo would generate lift, but that technology already exists and that's called a blended wing body, which is more of the focus towards future airliner and already has lots of money invested into it, and investing in a ufo would be too much money considering the amount invested blended wing body designs.

So I hope those 16 reasons helped explain why it would not be more efficient  than a modern day airliner and why it can't go into service. So the article was false for efficiency and other reasons.

I can't tell what you're trying to say.

I'm saying that they have tested a mini circular shaped model like a ufo in a wind tunnel and it wasn't very aerodynamic, if it used fossil fuels to power the aircraft it would not be efficient at all it would take a lot of fuel to power the ufo.

@Ethan Who said there was a correlation between time spent and quality of output? Rather than spend time listing everything that goes through your head, try to make sure that what you write is understandable to other people. But keep up the good work, your contributions to this community are overall getting better and better :)

@usernumber Thanks I will try to make every answer have this much thought and correct grammar mistakes so people can understand it. I took my old answer deleted everything and wrote a whole new answer thats more understandable and having  greater details.

@mins you know there is evidence of life once existing on mars. Weird figure shaped rocks have been found. I do believe this because mars did once have water and this society could have buried there kind into rocks so that another species could someday see it.

@Ethan There is no evidence of life on Mars.  There are some indicators that there might be evidence to be found but so far, none has.

They use the concept of VTOL thats vertical Take off and Landing. Click here to know more about VTOL
Regarding the efficiency, well I think no one can give a 100% perfect information on this because, we do not know the fuel used, the engineering behind the structure. There are a lot of factors affecting efficiency like :
Materials, Fuel, Type of Engine, Weight etc. So aerodynamics alone cannot judge the efficiency of the aerovehicle.
Thanks!

So aerodynamics alone cannot judge the efficiency of the aerovehicle. but the question specifically asks about the aerodynamic efficiency, not the overall efficiency.

authors: عاصم الخليدي


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How dedicated do I have to be to flying to get my privates rating
I am a new student pilot. I have flown for 3 lessons and my flight instructor asked me what path I want to take with flying.

What path do you want to take? You doing this for fun, or future job opportunities?

Do you mean in terms of learning, or future aviating?
I was always clear and open with my school that PPL was the target for me, with no interest to ever go commercial etc. There are plenty of PPLers who fly for nothing more than pleasure, and plenty who couldn't get a Class 1 medical.
If you mean dedication to learning - well, you aren't going to get a licence by accident but I didn't find the PPL path particularly onerous.


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What is meant by altitude correction above Transition level?
I am a system engineer dealing with Thales ATC product. In my system there is a server called sensor data processor, one of its function is to receive QNH data to do altitude correction. I can't understand this meaning since the system receives the Flight level from the Mode C which is calculated base on the QNH value given to the pilot from the ATC.

Above the transition level there is no need to correct the Mode C flight level, but below the transition level there is a need. Are you certain that your system will never ever handle any aircraft below the transition level?

My system handle the QNH. But I am confusing and have miss understanding about the meaning and significance of altitude correction.. I still confused. May you kindly discribe the meaning?

"Flight level" and "altitude" are not synonymous. They are two different concepts.
When aircraft are flying fast and flying high above the earth, pilots do not want to be constantly fiddling with the altimeter. So above a certain height, every aircraft has its altimeter set to the standard altimeter setting of 1013 hPa (29.92 inHg). When an aircraft is using this standard altimeter setting we say that it is flying at some flight level. Because the true altimeter setting (QNH) varies from day to day, any given flight level will move up and down relative to the surface of the earth. But that's okay because everyone is using the same standard and it doesn't matter if FL290 happens to be 28,600' or 29,300'.
But when aircraft are lower, it matters how high they are above sea level. In that case they set their altimeter to the local QNH, and the altimeter shows their altitude.
The transponder in the aircraft does not know or care what setting the pilot is using. It simply reads the outside air pressure and encodes that air pressure into an altitude assuming that the local QNH is standard. In other words, the transponder will always transmit the aircraft's flight level even if the aircraft should be using altitude instead of flight level. This means that your radar system must take the transmitted flight level and convert that into an altitude for display to ATC. In order to convert the flight level into an altitude, it must know what the correct QNH is.

It's  called Mode C correction factor.


text:
B737-800 wire routing path diagrams
I was wondering from where can I get screenshots of the aircraft internal fuselage without wall or ceiling panels showing the manufacturer wirebundle routes and ground terminal blocks like the pic attached.
I searched the IPC, WDM and AMM with no luck.
Lets say I want to get a screenshot as attached from station 360 to station 580 but for the left side of the aircraft, which manual should I check, if not within any manuals where can I get it ?


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How is fuel stored in a tanker aircraft?
How is fuel stored in a tanker aircraft? What arrangements are made to make the aircraft liquid tight?

What leads you to believe that extra arrangements are needed?  It just has more fuel tanks, which are like any other fuel tank,

I think the first answer in this question gives you a good image:
http://aviation.stackexchange.com/questions/9001/do-tanker-aircraft-distribute-their-own-fuel

How is flying boom connected to these extra tanks?

That will be a different question and you can ask that in a new post. Basically it is hose and pipe and pumps

You might be surprised to learn that most refueling tankers hold a relatively small percentage of their total fuselage volume in fuel. The reason why is simple; a plane stuffed to the gills with fuel would be so grossly overloaded it wouldn't make it off the runway. Tankers, therefore, can double as medium transports with little modification, as they have a sizable upper deck which is more or less empty space when serving as a tanker, but which can ferry troops, light vehicles or other materiel from Stateside bases to various theaters (a dedicated heavy transport like the C-5 or C-17 would be used for transporting large units or for specialized troop transport like airbornes).
Here's the layout of the KC-135 Stratotanker:

To my knowledge, all of this fuel is available both to power the plane and to refuel other aircraft, however the plane would likely draw primarily from the wing tanks for flight, as this is the "standard" configuration for the 707 the KC-135 is built on. Transport of the fuel from these tanks to the refueling systems would be accomplished with an integrated pump and pipe system that could move fuel from anywhere to anywhere.
The bulk of the fuel load, as you can see, is contained in four "body tanks" totaling over 144,000 pounds of fuel. For comparison, the F-15E strike fighter can carry a maximum, with CFTs and 3 droptanks, of just 35,550 pounds.
These tanks are lined with plastic bladders, which contain the fuel (so the entire fuselage doesn't have to be leak-proof which is much more difficult and expensive to ensure) and also allows the bladder to collapse as the fuel inside it is depleted, reducing the volume of air in direct contact with the fuel, thus reducing the vapor hazard. AFAIK the wing tanks do not have these bladders, but they're much smaller spaces overall and more easily accessed.
Separating the fuel into multiple tanks has several advantages:

The tanker is still serviceable with one or more of the tanks unable to carry fuel (leak in the bladder, pump failure, etc).
Sloshing of the fuel in the tanks has less effect on the weight distribution of the aircraft. Imagine trying to take off with a full Olympic swimming pool in your cargo hold; any pitch up or down will cause several tons of weight to move "downslope", unbalancing the aircraft (probably fatally).
Fuel can be pumped between these tanks to fine-tune or "trim" the aircraft's weight distribution and handling characteristics, a process known as "tank trimming" which is more aerodynamically efficient than elevator trimming.

Just a nitpick but few realize that the 707 and the KC-135 were both descendants of the Boeing 367-80 (the so-called "dash 80".  Siblings of the same parents but different in many ways.

In Vietnam the Air Force flew HC-130J's.  These were modified C-130 Hercules transports that were used in Search-and-Rescue operations.  Like all C-130's they had 4 turbo-prop engines, but they also had two jet engines, one under each wing.  In addition, they had extensive resources for doing search-and-rescue inside the airplane. They ALSO acted as a fuel tanker for SAR helo's and fixed-wing acft - a huge fuel tank in the cargo bay fed out to a refueling hose on each wing.  That hose had a basket on the end which the receiver a/c engaged, locked onto, then took a drink.

not sure how JT1000 comment is relevant, but the HC-130J doesn't have any jet engine, just the usual 4 turbo props:
https://www.lockheedmartin.com/en-us/products/c130/hc-130j-combat-king-ii.html
https://www.af.mil/About-Us/Fact-Sheets/Display/Article/104468/hc-130j-combat-king-ii/


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Why are military planes painted differently than civil planes?
I read Why are planes generally painted white?, and got interested in knowing, why don't military aircraft follow this? Rather than the advantageous white, most of the military aircraft are rather painted pretty darker, green or black or some other color. Why is this done?
Probably, it is not for distinguishing military with civilian aircraft .Becuase, the RADAR knows which aircraft is what.

However see also this answer about nuclear bombers.

In a nutshell, because civilian aircraft are painted to be visually distinctive, whereas military aircraft are painted to be visually indistinct.

For the same reason that GI Joe wears camouflage while Ken is dressed up like a peacock.

This wiki article speaks to this somewhat. In modern-day air forces, the paint job will depend on the mission the aircraft is used for. However, with the improvement of radar, visual camouflage is less important than it used to be.
Blacked-out aircraft

Some aircraft are paint black or nearly black for use in night missions. The F-117 (shown above) was painted with a radar-absorbent paint and also primarily flew at night, lessening its probability of detection. Other aircraft, like the special operations MC-130 and AC-130 are painted very dark grays or blacks to lessen their probability of detection since they are primarily used at night in support of covert missions, often at low level where visual detection is the main threat. Modern Examples: B-2, MC-130
Ground camoflauge

Some aircraft are painted to blend in to the ground. Some of these are those designed for low-level attack roles (like the Tornado pictured above), to limit the chance of visual detection by enemy fighters from above since their radar signature is unlikely to be detected so low to the ground. Others, like the now-retired Saab 37 Viggen, may be camouflaged to prevent detection when parked on the ground, as many were dispersed around Sweden, sometimes hidden in forests, to prevent single attacks from taking out many defenses. Many military helicopters are also painted either a patterned or dark green color to blend into forests. Some aircraft have been painted tan to blend into desert environments. Modern Examples: Su-25, Super Tucano
Air camouflage

Many air superiority fighters, and a large group of combat aircraft in general are painted in some way to blend into the sky. I have read that the human eye has difficulty picking a gray plane out against the blue sky (or grayish clouds), and most USAF and NATO planes are painted in some form of "Air Superiority Gray". Additionally, many will have different-colored tops and bottoms to help blend in from above and below. This excellent aviation.se Q&A talks about false cockpits on military jets that contribute to better dogfighting performance. Some aircraft, like the Su-27, may have several different grays and whites painted on it to break the aircraft's shape up. Modern examples: F-22, MIG-29
There may be other aircraft that have unique paint jobs to assist in a specialized mission - a darker color on one area to help with sensors, special coatings to minimize damage from a nuclear flash. Overall, it is not as common as it used to be for aircraft to be green - most US Military aircraft were green in color during the Vietnam War, but as the distance of aerial combat has increased, so have the camouflage schemes. Grays are probably the most common paint jobs now among military aircraft of many countries, with other aircraft having specialized paint jobs for specialized roles.

Good explanation.  I think the camo pictures would be a lot more instructive if the planes were a lot smaller though...

Military aircraft often are painted for camouflage effects.  Aircraft that fly night missions may be entirely black.  The top portions may be painted to make them more difficult to identify from the air while parked on the ground.
Different forces and missions have radically different priorities for the appearance of the craft.  Even though you can't make them invisible, simply increasing the time it takes to get a good visual identification can be an advantage for a military craft.


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How are aircraft filmed in sky?
We have several spectacular and amazing videos of aircraft, flying high in the sky.  How are these videos filmed, at great altitudes?

they use a slingshot to launch the camera at the aircraft and they hope to get a nice shot (pun intended).

With a long selfie stick ;)

Related: https://travel.stackexchange.com/a/64241/15281

Two words: chase planes.
A few more words: The easiest way to film an airplane in flight is with another airplane in flight. Here's one article on how that's done, including images captured from both sides; the chase plane (a Learjet 25B) getting the shots of the 787 Dreamliner, and crew aboard the Dreamliner getting a few snapshots of the chase plane.

Early shots taken from chase planes often used simple handheld cameras; a two-seater would normally be used with the pilot in front and the photographer in back. This is still a totally viable way to do it, but more modern professional shoots utilize aircraft specifically modified for the task by adding internal or external camera mounts, optical-quality viewports, etc. Here's a modified T-33 used by Boeing specifically for air-to-air photography, including some of the initial publicity shots of the 787 in flight; notice the camera mount between the seats that can be used by the GIB (he's using a handheld in this photo:

For lower-speed shots, you can also use a helicopter. Many of these such as news choppers have remote-control cameras on gyro-stabilized mounts, so the vibration of the airframe is minimized in the shot even at high zoom:

These same camera systems can be used for air-to-air shots as well, however the maximum airspeed of the helicopter becomes a limiting factor. Still great for publicity shots of small prop planes, or takeoffs/landings.

And then there is third airplane in flight to do behind the scenes.

That helicopter looks like it's smoking a pipe.

I film all my stuff (from inside the plane) with a GoPro. This seems to be the common way the smaller guys are doing it. There are companies that make mounts that will even hold the camera on outside a plane. You can check out this post from Sporty's on the matter.  Some of the stuff shot by the pros may be taken from another plane or a helicopter. The news choppers I see leaving from KPNE have the newer nose style cameras that I assume they operate from the inside of the chopper.

You are not specific in your question, so there are many ways that aerial footage can be captured.
As Dave mentions, GoPro cameras have gained popularity especially with private pilots. They are relatively cheap, small, easy to use, and capture good quality video. Many videos from inside the cockpit or outside use cameras like these.
Air to air footage is taken from other aircraft. For the most flexibility, a fighter jet is a good choice. You could also shoot through the door of a smaller aircraft. Helicopters are best at lower altitudes and speeds but are good for filming takeoffs and landings.


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Can flight crew book tickets for themselves, on the same flight?
Is it possible that flight crew book a ticket for themselves, for say utilizing their rest time better (like Emirates offers mid air shower to first class passengers, but not to crew)?

They could book it but why would you? The cost of a seat is almost certainly more than the pay for the flight so it would be a waste of money.

If the flight was full, every airline int he world would bump the flight crew to make space for an extra passenger. If the flight wasn't full the crew could go and sit in the spare seat if it was considered appropriate.


text:
How do ferry flight operators like Nomadic Aviation maintain type rating for their pilots?
The recent VT-EVA ferry flight from BOM-Paine Field - US desert really piqued my interest about how the crew are arranged for such flights?
B747-400 is a pretty rare aircraft now a days, and I don't think most scheduled airlines allow their pilots to freelance. Nomadic Aviation on their website mention they have a dedicated crew of 30 pilots
Yet, how do these pilots maintain their type ratings given they often fly unique aircraft only once in a 3 or 6 month period. How do they satisfy requirements of 70 flying hours to maintain type rating?
I did refer to Who flies planes on ferry flights but the answers there don't exactly focus on qualifications of pilots for ferry flights.
Is it the case that ferry flights are exempt from exact type rating requirements for pilots somehow?

Ferry flights use different regulations in most jurisdictions. No need to be “current” on type.

I would assume they apply for a waiver.


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What is the point of having lots of different flaps settings?
This question is about the number of flaps settings on different airliners. One can notice that this varies greatly between models and manufacturers. On a Cessna 172, you usually only have 4 or 5 settings.
But on airliners you have usually more, especially on Boeing.
So I did a quick search and found the following (links point on the image I used):

B777: 7 settings: 0-1-5-15-20-25-30
B737-900: 9 settings: 0-1-2-5-10-15-25-30-40
B787-8: 7 settings: 0-1-5-15-20-25-30
B787-9: 10 (!) settings: 0-1-5-10-15-17-18-20-25-30

On the other hand, Airbus seems to stick to the same scheme for its models:
 the A320/A330/A350/A380/A330 all have 5 settings: 0-1-2-3-full
The questions are:

When you have 9 or 10 different settings, what is the point of having so much ? Is that really useful ? Does the crew really incrementally uses all of them on approach and landing ?
I mean, if they only step, say from 0 to 5 on approach, then  5 to 15 on long final, and then 15 to 30 on short final, then the manufacturer could have saved some metal.
Boeing planes have more settings than Airbus. Is there any particular design reason behind that ?
Airbus doesn't designate the different positions as angles, but as incremental numbers. Anybody knows why they did that design choice?

Why Airbus only uses 0-1-2-3-FULL: I think they do this because they are wise and want to support pilots in their work. Its the same with the ECAM they invented. Genius, awesome inventions that makes life for Pilots so much easier and safer.

@NoahFisher Sorry but this sounds like a rant: I don't see the relationship between using sequential numbers instead of angular positions and supporting the pilots in their work. The question is not about which design is better (if there is any that would qualify as so).

@Noah what do Boeing EICAR and Airbus ECAM have to do with the question? Note: flaps don't just rotate, they also extend, and there often is more than one per wing. The flap "angle" on Boeing airliners is just an arbitrary number that incompletely (and inaccurately) describes the flaps actual position.

The Airbus scheme is 0–1–1+F–2–3–Full. The lever position 1 selects different configuration depending on other conditions.

@kebs Yes, it is a rant too. I don't like Boeing. But he also asked if there is a particular design reason for the Flaps Position Levers. I am not an engineer at Airbus but I think that they want to keep it simple. As everything in this amazing airbus planes.

@RedGrittyBrick It just was a comparison. Airbus makes things simple and intuitive. In Boeing you got this mass of flaps settings, in Airbus only a few, nicely numbered. In Boeing you have to look on a mass of gauges and displays. Airbus merged everything into the beautiful ECAM.

Re "On a Cessna 172, you usually only have 4 or 5 settings", it's been a long time since I've flown one, but IIRC you actually have a continuous range of settings, since they're electrical.  Unlike say my Cherokee, which has notches in a manual lever.

@jamesqf Its been quite some time I've flown one too, but I think you are both right... and wrong: the flaps are indeed electrical, so you can theoretically make them stop at any position, but the selector has some fixed latched position, so you usually stick to those (see http://www.privatepilots.nl/phvzv/40flaps.gif )

1a. On take off, with a light airplane you may select less flaps to reduce the additional drag and save some fuel. Max takeoff flaps are reserved only for short runways and high loads. Fuel savings are very important nowadays.
1b. On approach, less flaps produce less noise and may also allow a higher approach speed (VFE is the maximum flaps extended speed and may be different for different flap settings). Maximum flaps are set only later in the approach when the plane has stabilized at the final approach speed.
1c. The flap setting has an effect on the airplane's pitch angle. A certain flap setting may help to minimize the tailstrike risk. The longer B787-9 has nine settings, while the shorter 787-8 has six.

I learned the Boeing numbers are not true angles either. For example, settings 1 and 5 may only affect the leading edge slats. At higher settings they approximate the actual angles (which are anyway somewhat misleading in the case of today's multi-part Fowler flaps, which move both down and backwards).

https://www.flightglobal.com/news/articles/farnborough-aero-secrets-of-boeings-new-dreamliner-401784/
http://www.boeing.com/commercial/aeromagazine/articles/qtr_4_08/pdfs/AERO_Q408_article05.pdf

On point 3, neither the Airbuses position are related to flaps angles ONLY, for instance the second flap position on the A300/310 ("15/0") means 15° slats, kruger flaps extendend, 0° flaps and 7° ailerons droop.
Source: A310 FCOM.

Airbus doesn't designate the different positions as angles, but as incremental numbers. Anybody knows why they did that design choice?

Probably because flap angles are basically lies.
Airliner wings don't just have one flap that only rotates. They have multiple flats and slats, the flaps extend as well as rotate. The pilots don't need (or want) to know the full multi-dimensional details of the positions of all the individual elements.
The same is true for other control surfaces. Particularly as they can vary dynamically to even out loads.

Position    Slat     Flap
0           0        0
1           18       0 when selected above 100kts. (approach)
1           18      10 when selected below 100kts. (takeoff)
2           22      15
3           22      20
FULL        27      35

The actual angles depend on what engine the aircraft has (e.g. CFM vs RR) and may be different angles for different variants of the aircraft.

The inner and outer flap elements are not mechanically coupled with each other and are controlled independently of each other for the purpose of setting the span load distribution. The system also comprises a flap control that controls the angle of the outboard flap element, independent of the inboard flap element, for optimizing a lift to drag ratio during aircraft takeoff and landing.

Airbus patent
There's something to be said for not confusing pilots cross training onto a new aircraft type or minor variant. Maybe having 0 1 2 3 FULL be used the same way across a large number of aircraft makes pilot's lives easier and makes errors less likely.

Airbus aircraft have five flap settings. They are:

Flaps 1.
Flaps 1+F.
Flaps 2.
Flaps 3.
Flaps FULL.

The setting for flaps 1 and 1+F are controlled by one position of the flaps lever. When flaps 1 is selected on the ground, the slats and the first stage of flaps extends. Hence the name 1+F. The 1 stands for the slats and the F stands for the flaps. In flight, things are different. If you extend flaps 1 in air, you will only get the slats. The flaps start moving out only when you set the flaps lever to 2. This I believe is same for the Boeing 777. Moving the flaps lever to 1, in the 777 only moves the slats. This makes the flaps 1 position of the aircraft redundant on the ground because you cannot take off with slats alone. Airbus on the hand changed the slat and flap computer logic so that the same flap lever position demands two separate settings depending on the phase of flight. So, it is a bit of clever design.
As for why Airbus designed flaps lever like so is because they wanted commonality across their aircraft. I fly the A320 and the A321. The latter is 15 tons heavier than the other but my call outs for both the aircraft for flap selection remains the same. It is Flaps 1,2,3 and FULL. It is the same call out for the A330, A340, A350 and even that massive A380. The flap slat angles are of course different for each of these aircraft. The flap lever positions are just settings. They do not really correspond to the actual flap or slat angle.

There are also many Airbus operators that opt for mixed fleet flying where A320 pilots also fly the A330. Having similar call outs and operating procedures helps the pilots in flying two different aircraft at the same time. And also, because Airbus aircraft have so much in common, the type rating time frame is reduced if a pilot already flies an Airbus aircraft. For example, to go from flying an A320 to an A330 takes just 3 simulator sessions and some ground classes. The course will usually be done within a week. If you compare that to a normal type rating course it is four times shorter.

Thanks for these interesting insights of Airbus design choices!


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Why is the first letter of Kosovo's airports "B"?
Generally, the first letter of ICAO airport codes indicates the region an airport is in.

There are a few exceptions, though most can be easily explained. However, I have not been able to find any documentation on why Kosovo's Pristina International Airport has ICAO code BKPR, geographically putting it in the Arctic (compare to Keflavík International Airport BIKF) while the rest of south Europe has code beginning with L (compare to Istanbul Airport LTFM)
Perhaps it has to do with the fact that Kosovo isn't an ICAO member?

Looking at your linked list, you see the simple issue that they ran out of L's. LA through LZ have been assigned.
E's are still available, but that would cause an out-of-geography country. B's as an overflow seem to be the choice they made. A factor is there's relatively little traffic to Greenland and Iceland, so the disruption in the B's come up less than with E's.

If you look at the list you mentioned, you can see that the other "late comers" had to contend with the letters that were still left, even though they don't fit the country names: LD - Croatia, LJ - Slovenia, LQ - Bosnia and Herzegovina, LU - Moldova, LW - North Macedonia etc.

Also using the B prefix lets them use K for Kosovo. That would not be possible with the E prefix (EK is Denmark).

It isn't unheard of for countries to have the same two-letter prefix (ex. FM for Comoros and Madagascar, or more relevant LY for Serbia and Montenegro. Montenegro became independent from Serbia in 2006, while Kosovo declared independence in 2008, so why wouldn't Kosovo share Serbia's code just like Montenegro?).

@astroleaf Serbia and Kosovo aren't apt to share anything. Serbia doesn't recognize Kosovo. They kind of had a war in 1998 that killed thousands. NATO still has troops in Kosovo today to keep things under control. Additionally, Kosovo isn't universally recognized by other countries, having to share is a sign of the ICAO/UN saying it's not a legitimate state. The relationship between Serbia and Montenegro is very different.


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What exactly is the FLS on the A350/330?
And how does it differ from the classical A320 Final App?
By FLS I mean FMS Landing System.

The FMS Landing System (FLS) is part of the Airbus xLS concept, which uses very similar indications and modes for any straight-in approach regardless of the underlying guidance system. This includes ILS, GLS (GBAS Landing System), SLS (Satellite Landing System) and FLS:

Airbus Strategy for Straight-In approaches
Similar displays whatever the modes

(Airbus Fleet Readiness for GBAS/SBAS)
This allows pilots to fly almost any approach in exactly the same way:

The creation of new approach modes that have lateral and vertical profiles independent of navaids followed the introduction of the Flight Management System (FMS) in the 1980s and of the GPS in the 1990s. The objective was to standardize the way of flying all approaches down to the published approach minima, whatever the airport, and whatever the equipment on the ground. The FLS (FMS Landing System) is part of that concept and today, it is an Airbus option offering a solution to fly 99% of approaches that are not ILS/MLS, with a barometric vertical profile.
It offers lateral and vertical guidance for a straight-in instrument approach, referenced from the aircraft position, along a trajectory retrieved from the FMS navigation database.

(Airbus: Safely Flying Non-Precision Instrument Approaches)
The FLS system is designed to calculate a fake localizer and fake glide-slope signal based on a non-precision approach coded in the FMS database:

FLS replicates the ILS beam concept, but using only the onboard navigation sensors with no need for additional ground aids. The FMS constructs a “pseudo beam” which has an anchor point (not necessarily aligned with the runway threshold), approach course and Flight Path Angle (FPA), and which overlays the final segment of an instrument approach with a temperature compensation on final segment for the indicated altitude.

FLS allows a pilot to fly an approach down to minima as an ‘ILS-alike approach’ thanks to the CDFA technique. In addition, the human / machine interface has been designed similar enough for the crew to capitalize on their current techniques but different enough for the crew not to mistake a non-precision approach flown with FLS for an ILS thanks to a distinctive symbology. In the end, this concept makes these approaches more simple to fly, thereby contributing to an increase in safety.

A characteristic of the FLS is that it can only be used for straight-in approaches but it is not compatible with curved RNP-AR approaches. Indeed, for curved approaches, crews need to undertake specific training and checking, and use the FINAL APP (or APP-DES on A350 aircraft) mode.

(Airbus: Safely Flying Non-Precision Instrument Approaches)
So only RNP-AR approaches with RF (radius to fix) legs on final cannot be flown using the FLS, any other straight-in approach works. For the curved RNP-AR you would use the traditional method (e.g. FINAL APP on A320).

Boeing has a very similar system called Integrated Approach Navigation (IAN). See also What is the difference between IAN and LNAV/VNAV?


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A220 roaring sound
I have noticed that the A220 makes a very roaring noise when the engines spool up from idle. Definitely distinctive compared to other aircraft.
In fact, it gets to the point where I can hear this noise for 5 km outside the airport as the only regular sound.
If I can hear it, surely others can hear it too, which leads me to wonder how this distinctive sound is created and whether efforts are being made to reduce its volume.

The A220 uses essentially the same geared turbofan engine as the A320neo, do any of those fly into the same airport for comparison? According to Wikipedia the A320neo uses the PW1100G, 20 blades, fan diameter 81 in (206 cm). The A220 uses the PW1500G, 18 blades, fan diameter73 in (185 cm), and lower thrust.

Yes, I live near Hamburg Airport, to which many A320 (Neo), 737 and other similar fly. None of them compares to this sound. Every time I hear the sound, it's an A220 according to FR24.

Maybe it's thrust reverser or gear vortex shedding? Especially vortex shedding would explain the difference between A220 and A320, as they have less in common aerodynamically than engine wise. https://aviation.stackexchange.com/questions/93373/hearing-an-deep-hum-sound-is-it-the-reverse-thrust-deployment-noise

The A220 is powered by Pratt & Whitney PW1500G engines.
According to Pratt and Whitney, the noise is a "low-power transient combustor tone caused by pressure changes against the combustion structure."
The resulting effect and sound is similar to blowing over the opening of a bottle.
P&W do say it is more noticeable because the PW1500G is relatively quiet otherwise.

Thanks for the information. I can confirm the sound, but I cannot agree with P&W's statement. This sound is definitely much louder than most other aircraft flying to Hamburg. The volume compares to the 777's startup sound.

yeah - I agree. The ones I heard certainly seemed louder (to me) than many of the other aircraft engines.

That second sentence is copied from my answer to a question that asked the same thing, is this a duplicate?

@AadirajAnil - I've not seen your answer. I found that, and similar wording on a couple of aviation sites. Can you pop up a link?

It's almost a turboprop with a fixed pitch propeller with lots of blades. The core engine is quite small compared to most turbofans and is putting a lot of air through at high velocity, so the sound out the exhaust tailpipe is loud.

@RoryAlsop my answer is also from the same sites that you visited, I'm saying, is the question a duplicate since the answers match up so well?

@AadirajAnil - is it a duplicate of what? I can't find another question on the A220 roaring sound on aviation.SE

The sound you are hearing might be due to the variable bleed vanes as well as the variable stator vanes that help direct airflow and change position depending on the power setting. It is also found on other engines that have a similar TALON combustor to the PW1500G like the PW800. It is likely due to the sound harmonics of the engine as well.

Is this a statement of an answer to the question, or is it a guess? If the former, please provide a reference for what's being presented as factual. If the latter... please don't post guesses as answers.


text:
A/FD Landing Weight Codes
The airport for the example shows only an S-17 for the runway bearing strength code in the Chart Supplement (A/FD). I understand this to mean single wheel per leg up to 17000lbs total landing weight.
Does this mean that “tandem or dual wheel” configured aircraft or larger can’t land there since it isn’t listed?
I remember vaguely a single wheel equivalent somewhere but didn’t know if someone had a reference to point me in the right direction or on any regulations regarding the matter.

The document does not indicate aircraft are not allowed, this is the other way around. It indicates what are the types known as allowed, as reported by the airfield owner. Other types may be allowed but this is unknown. From the Chart Supplement:

When different wheel configurations have been evaluated, they are all listed, e.g:

RWY 02–20: H6000X150 (ASPH–GRVD) S–66, D–150, 2D–336

If aircraft with some wheel type can land, but the maximum weight is unknown from FAA, this is indicated by leaving the figures blank, e:g: S–66, D-.

AUW All up weight is used as an indicator strictly based on weight:

Maximum weight bearing capacity for any aircraft irrespective of landing gear configuration.

RWY 173–353: H3515X150 (ASPH–PFC) AUW PCN 59 F/A/W/T

SWL Single Wheel Loading

Information submitted in terms of Equivalent Single Wheel Loading (ESWL) and Single Isolated Wheel Loading)

(no example found)

In any case

When desiring to operate into any airport at weights in excess of those published in the publication, users should contact the airport management for permission.


text:
Maximise Range Vs Pitching Down while flying a Glider in a Downward Air Mass
While flying a glider, if I encounter a downward moving air mass (i.e. sink) while on final, should I fly to maximise range (best lift to drag ratio) or should I pitch downward in order to exit the sinking air mass as quickly as possible, so that I do not lose too much altitude? A technical explanation would be appreciated. Thank you.

https://en.m.wikipedia.org/wiki/Speed_to_fly

Simple trigonometry will answer your question.  You have to add the down draft velocity to your sink rate.  A higher glide speed has a higher sink rate than Vbg, but gets you out of the downdraft faster.

Unless you are an advanced pilot you should never be having to think about this question in flight.


text:
How many flight training hours can a student realistically do in a week?
How many flight training hours can a student realistically do in a week?
I have 11 PIC flight hours (and solo'd at 7hrs) but I havent flown (PIC time) since 2008. I want to finally get my license but am unsure if I can realistically do it before I leave the country in one month.
In one week, I can actually devote my entire day to flight training so I'm wondering how many PIC flight hours a student can realistically do in one day and thus a week. Is 2-3hrs flight time (2-3 actual sorties) for 7 days realistic?
Also, I know this is highly dependent on my CFI but let's assume I can find one to match my speed...

There are a few external factors

Your CFI:
If we are talking about dual time (or supervised solos) here your CFI will need to be free.
The plane:
Keep in mind that school may have other students who may also book the plane, or it may be out for its 100 hour inspection or it is broken etc.
The weather:
Depending on where you are located, you may be limited by the weather grounding you for VFR flight.
The Wind:
A lot of flight schools (at least the one I go to) impose student maximum limits when it comes to crosswinds. At single runway airports this could cause an issue. You can mitigate this by training at a place with two runways.

Now if we look past all those and assume you have a working plane, a CFI, and clear weather, then I would think (assuming the school is open) you could log 3 hours in the morning and 3 in the afternoon if you really pushed it. If you started your day with 1 hour of ground from 8-9 then flew from 9-noon. Lunch. Then another hour of ground from 1-2 and flying from 2-5 that is putting you at close to 6 hours a day. Throw a few night flights in there, some more ground lessons at night and you may be able to squeeze the time in. Keep in mind you will also need to study for the written exam.
Note: The above projection is strictly based on everything working all the time which in aviation is often not the case. Your results may vary.

Are you thinking that the hour of ground before the flights is going to be sufficient to give them the theory for the next flight, or for preflight type activities?  One of the biggest limitations in my mind would be the theory and understanding what you are about to go do before you do it.

If you are diligent about reading the text the night before and prepping for the longer lessons with an hour of ground the night before I fell it could be done. Granted YMMV and some will pick it up faster than others.

Is 2-3hrs flight time (2-3 actual sorties) for 7 days realistic?

I think that's do-able.
A typical flight lesson is about 1.0-1.5 hours of "flight time", with a pre-brief and post-brief to go over the lesson. If you do 2-3 of those you'll be in the air somewhere between 2 and 5 hours, and spend another 1-2 hours on the ground. Add in time for lunch and stretching your legs between flights and you've filled an 8 hour day with training.
How effective that training will be is a different story.

I did a lot of "double header" days when I was wrapping up my training: I would go up with my instructor in the morning, have lunch, then come back and solo for an hour or so working on the stuff I needed to work on.
I think that was an effective way to finish up (because I was working on specific targeted things).
Since you're effectively a "post-solo" student I think you'll fall into this box: Spend a day or two with an instructor getting the rust off your skills and getting signed off to solo again, knock out your cross-country and night requirements if you don't have them already, and then split your remaining time between flights with your instructor doing checkride prep & solos working out the kinks.
2-4 hours in the air and as much classroom & study time as it takes might get you there - if not you can continue the training in your spare time (before/after work or whatever other activities are tying you up for the rest of the month).
Remember you'll also need to find an examiner to give you your checkride, so plan for that (sometimes they're booked out pretty far in advance).

The flip side of the coin is that I also did a few "double-header" days early on in my training (pre-solo), where my instructor and I would book a 4 hour block and spend 2.5-3 hours in the air.
The extra time in the air was fun (it was enough time to go visit other airports), but in retrospect I don't think it was anywhere near as effective pre-solo as it was post-solo: When you're first learning to fly 1-2 hours in the air each day is about all your brain can handle (at least it was all my brain could handle), and then you need to take the time to digest what you learned, read over the lesson materials, and let the knowledge soak into your head.

I agree wthat the pre-solo training flight time of 1-2 hours is good.


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What is the difference between Part 135 and Part 129?
I work with small commercial aircraft. Up until now I have understood Part 91 to mean that the flight has been filed as private and Part 135 to mean that the flight has been filed as commercial, to put it simply.
Recently, after a problem I can't go into, my colleague suggested that the problem could have been caused if the carrier was not "Part 129 approved".
What is the difference between Part 129 and Part 135?
Are there any cases in which you would need one and not the other, or both, or neither?
Are there any other "Parts" that can affect a foreign carrier flying to/from/within the US?

Part 91, 129, and 135 are not related to what the aircraft files as, they relate to the standards and regulations by which flight operations are conducted. Have you read through 129 and 135?

I'm not at all sure what you're asking, but maybe I can at least point you towards more information.
First, the parts you mentioned define operating rules for different flight types (I'm simplifying a bit here):

Part 91: rules for all flights in the US
Part 121: rules for flights by a US airline
Part 129: rules for flights by a foreign airline in the US
Part 135: rules for 'on demand' (usually charter) flights by a US operator

Any given flight will operate under one or more of those sets or rules, e.g. a US airline flight from New York to Los Angeles would follow the rules in parts 91 and 121; a foreign flight from London to New York would follow parts 91 and 129 (while in US airspace). Individual operators and airlines also have OpSpecs that are approved by the FAA and that can add more rules for specific situations.
And I'm not entirely sure, but it looks like 14 CFR 129.119(c) effectively applies part 121 to foreign airlines too, by requiring them to comply with the same rules as US airlines:

(c) Each foreign air carrier shall conform to the practices,
  procedures, and other requirements prescribed by the Administrator for
  U.S. air carriers for the areas to be operated in.

Without knowing what your mysterious problem was (and I understand you can't share it), I don't think it's possible to say much more than that.
(By the way, "filing" is something different. Filing a flight plan is required for various reasons but they apply to all aircraft, even private flights. If I want to fly a C172 under IFR then I have to file essentially the same flight plan information that an A380 pilot will file.)


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What are some of the easter eggs on the FAA pilot license?
I know that the back of the card has a hidden speech along the Wright brother's collars and the Wright flyer's frame. Also, if you shine a black light on the card, there's an (invisible to the naked eye) imbued text that reads "FLY SAFE". Are there any other easter eggs to be found?

Those aren't "easter eggs," they're anti-counterfeiting features.

Are there any other anti-counterfeiting features? I know there's also the FAA hologram thing on the front as well.


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For transporting 4000kg of cargo via Mi-17 helicopter for 54 km, how much maintenance cost per flight hour will be incurred?
In a disaster response case study, I am using Mi-17 helicopters for relief supplies transportation in a challenging logistics environment.
Regarding this, I want to check my estimates with the actual operational experience that community members may have..

I recommend you to contact a transport helicopter company or a SAR base. I suspect you need to discuss many items (and there is much logistic involved, so you may be very interested in it). This site is maybe not ideal (answers may not be connected to previous answers or questions, or answers may go in a direction you are not interested.

Ok dear got it!!

Maintenance cost is part man-hours, part hardware replacement. The first part depends on who's doing the maintenance, the second on how much flight hours the helicopter gets per year, since parts have both flight hour based and year-based replacement requirements.
This discussion lists Mi-8 rates being between $1,050 and $4,500/hr in '05. Fuel burn is 650-900 liters per hour - use 750 for cost estimates, 900 for flight planning. The Mi-17 is basically an upgraded Mi-8. The costs have increased since, due to higher wages and the exhaustion of spares from military-surplus machines.
For study purposes, you could optimistically estimate it at $2,500+fuel for CIS and China, about $3,000 for Asia, Africa, South America and East Europe, about $5,000 for the EU, and $6,000+ for North America and Australia. Add fuel. The difference is due to different availability of maintenance expertise and parts.
These are peacetime numbers. The costs are higher at the moment, due to high demand + trade disruptions. They will probably stay at about 1.5x for neutral/RU-aligned and further higher for US-aligned countries until the things boil over. They might not come down quite to the old levels, so I'd give it some risk adjustment to be safe.

for Asia, is it $3000 per flight hours?

I would estimate it at that, in the context of an academic study (long-term). Short-term, you would need to check with a local company. It's more expensive than it used to be, but still very competitive.

got it, long term value will be better

$3k is long-term. Right now it's more, the wait time for spares is longer.


text:
How much fuel cost will be incurred for transporting 4000kg of cargo via Mi-17 helicopter for 54 km?
I am working on a logistics case study in which I am using Mi-17 helicopters for transportation of relief to the affected areas in a disaster.
In this regard, I want to check my estimates with the actual operational experience from the community..

The question title specifies fuel costs, but those are probably among these least of the costs of a project like this. What about maintenance costs? What about paying for the use of the machine, pilots, crew, etc? Any operational experience will tell you as much about these costs as about merely the fuel cost in isolation.

Actually I am finding it difficult for determining the maintenance cost (hourly), can you help me with this?

Can you help me in setting the maintenance cost per flight hour with some reference? I am getting numbers from ChatGPT but I cannot cite them

According to this source, the Mil Mi-17 does about 465-495km at standard load with the 1870l internal fuel. This equates to around 4l/km.
Currently, the fuel price for a liter of jet A1 in the US is $0.559. Therefore:
$54km \cdot 4 \frac{l}{km} \cdot  0.559 \frac{$}{l}  \approx \\\$120 $

On such a short hop, the takeoff and landing add a substantial amount of fuel consumption. I bet I'm not too far off to say you could almost double the cost. Helicopters are super inefficient in vertical flight.

So can you give an estimate based on some reference